Rotary gas-engine.



JT. J. MGTAVSH, JR.

ROTARY GAS ENGINE. APPLIUATION FILED D'BG.5,1912.

Patented. Jan. 12, 1915;

I 3 SHEETS-SHEET l.

J. J. MGTAVISH, JR.

ROTARY GAS ENGINE.

APPLICATION FILED 1330.6, 1912.

@4.9% Patented Jan. 12, 1915. s SHEETS-SHEET 2.

l y l i...

J. J. M GTAVISH, JR. ROTARY GAS ENGINE.

APPLICATION FILED DEG.5,1912.

1,1 24,4%. I and aan. 12, 1915.

3 SHEETS-SHEET 3.

WITNESSES JNVE'NTR.

ATTORNEY I UNITED STATES y TENT UFFQE.

JOHN J. MGTAVISH, JR.; OEDETROI'B, MICHIGAN.

ROTARY Ci'AS-ENGIN E.

- ings, which form a part of this specification.

This invention relates to rotary gas engines of the four cycle type inwhich the explosive mixture is introduced between the ends of opposingpistons in a single cylinder. The cranks at opposite endsl of thecylinder are each provided with a gearv meshingwith a 'stationary gearwhereby the cylinder is made to rotate and a shaft is secured to thecylinder whose axis is coincident with the axis of rotation of thecylinder.

A further object of the invention is to eliminate the usual cams androds for operating the inlet and` exhaust valves which isaccomplished byutilizing a rotating valve in'communication with the interior of thecylinder between the two pistons therein, and the relation of the gearsis such that two complete cycles of operation of the engine are producedduring a single revolution of the cylinder. Bysuch arrangement 1multiplicity. of parts is avoided-and the combined momentum and power ofthe rotating pistons and cylinder is transmitted to the shaft from whichit may be utilized in any well known manner.

. These and further objects and novelties of the invention arehereinafter more fully described and claimed and shown in theaccompanying drawings in which- Figure 1 is a vertical section of anengine embodying my invention.- Fig. 2 is a side elevation partly insection showing the rota-ting valve and ports controlled thereb and aportion of the stationary gear witi which the gears on the crank shaftmesh. Fig. 3 is a side elevation showing the casing in section and adiagram of the 'electric circuit by means of whiclt the explosive chargemay be ignited. Fig. 4 is a detail of the contact pin through or bymeans of which current may fiow tothe spark plug. ig. '5 is an elevationof the commutator v Specification of Letters Patent.

Application aled December s, 1912. serial No.

vof therotary valve.

plate. Fig.. 6 is an enlarged cross-section Fig. is a detail showing theshape of the port in the valve. Fig. 8 is a detail of an alternativeform of the device. i

Similar characters refer to similarparts throughout the drawingsand-specification.

he engine consists primarily of a stationary casing 1 provided with abearing for the shaft 2 to which is secured the cylinder 3. The cylinderis preferably provided with a lining 4 and the shaft terminates at thelining as shown in Fig. 1. Like pis- Patente-d Jan. l

tons 5 are mounted in each end of the cyl-V inder connected by the usualconnecting rods to a crank shaft 6 mounted in crank cases 7 secured toopposite ends of the cylinder. Each of the crank shafts is provided witha spur gear 8 meshing with a stationary gear 9 secured to the casingwhose center is coincident with the the rotation of the crank shafts byreason of the reciprocation of the piston produces a rotation of thecylinder andpistons due to the travel of the gears 8 about themastergear 9. In this connection it is to be noted shaft center and thatthe crank shafts should be slightly offset in their relation to thepistons in the di- 'rection of rotation of the cylinder in order that anexplosion between the two pistons cannot take place on the dead centerand therefore each gearSwill rotate in the same direction and producethe desired rotating movement of the cylinder. The cylinder is providedwith an aperture itl-.leading into the explosion chamber in thecylinderbe tween the ends of the pistons therein located directly oppositethe-'shaft 2 and in line therewith and mounted on the cylinder in axialalinement with the shaft is a cylindrical rotary valve 11 provided witha passageway leading to the port l0 in the cylinder. The valve is seatedin a. chamber provided therefor in the casing and serves as a supportfor the cylinder in addition to the support provided by the shaft 2. Asshown more fully in Fig. 2. there are two intake ports 12 and 13 and"two exhaust ports 14A and 15 provided with passages leading into thevalve chamber and the two intake ports and' the two exhaust ports may'be connected-bv a manifold to a single' intake and single exhaust linesrespectively. the exhaust manifold being indicated by dotted with a port1G leading to the central .passagevvay and this port 16 in the valvesuccessively registers with each of the intake and exhaust ports during5 revolution thereoic and the operation is as. follows-When the port 16is in registration WithY 'the intake port 12 the pistons' aretraveli'gputward in the cylinder thereby dravvinga charge thereinto. Asthe port lrontinues its movement the charge in tlieicylinder iscompressed and ignited and the relationl ot the gears 8 to themaster-gear 9 ist such that this cycle of operations is'completed whenthe port 16 registers with the exhaust port 14 and the cylinder'exhausted of burnt gases and as the valve continues its movement andcomes into registration with the intake port 13 the pistons are again onthe intake stroke and the cycle of operations again completed at thetime the port is in registration with the exhaust port 15 vand these twoexplosions occurduring each revolution ot the cylinder. The charge inthe cylinder is ignited by means. of 'a spark'plu'g 20 positioned midway'between the pistons therein as shown in Fig. l and currentvmay besupplied to the spark plug in any manner usual With gas engines, onemethod of which is shown diagrammatically in Fig. 3 in which oneterminal of a spark coil is connected to both contact plates 21 and' 22mounted on Aa commutator disk Q3 which is loosely mounted on a cylidrical hub 24: on the cyl- 3.5 inder. To the dis'reis secured a pin Q5to which is secured in any convenient manner an operating rod 26 wherebythe disk 23 may be positioned in a manner to advance or retard the timeof explosion. Mounted on the cylinder and insulated therefrom, as shownmore clearly in Fig. 4, is a spring pressed contactv pin carried in theblock Q7 secured to the insulating plate 28 and this pin is continuouslyin contact with the disk lli ' 45 23 and during the revolution of thecylinder contacts the plates 21 and 22 at the proper intervals to ignitethe compressed charge.

ln order that no loss of compression may take place'through the port 16and the interstice between the valve 11 and the chamber in which itismounted, 'the valve is provided with Ia circumferential groove 30 aboutthe port 16 and a packing ring 31 inserted therein and this ring 31 isheld in contact with the wall of the chamber by means of the coilsprings 32 as shown in Fig. 6, and a leakage through the port therebyprevented. `The port, as shown in Fig. 7, is longer in the direction ofits travel than transversethereto, and by this arrangement the intakeand exhaust ports Which are substantially of a diameter equal to theWidth l of the valve port, are practicallyA fully opened as the 'forwardedge of the port in 65 the valve passes the edge of the intake port asingle l ternative ideate-t termed wire 'draw 1 and prevents what isopening and closing from lthe 4other part of the casing whereby 75 I'the valve and other portions of the mechanism are accessible forinspection or repair.

vVVhile I have described the crank as having but a single gear thereonmeshing with a stationary may be formed as shown in Fig. 8 with a gearupon each end thereof meshing With stationary gears correspondingly.positione upon opposite sides of the casing, such al- :torm of thestructure, being of 85 greater strength and the cranks are alsoreli'evedof excessive side strain.

While I have/.shown asimple vmethod of electric i gnitioii/ it is to beunderstood that any well known method or device may be used for thispurpose Without departing `from the spirit of this invention.

Having thus described my invention and its method of operation, what Iclaim and desire to secure by United States is- 1. ln an internalcombustion engine, a cylinder mounted for rotation abouty an axis,pistons in said cylinder in opposed relation and arranged forsimultaneous actuationby an exploded charge, a crank shaft forl eachpiston mounted at the opposite ends of the cylinder, a gearA on eachcrank shaft, a stationary gear mounted concentric with the axis ofrotation of the cylinder With which said crank gears mesh, a port insaid cylinder Whose .center is coincident with the axis of rotation, avalve cylindrical in formele-- cur'edvto the cylinder provided with apassageway leading,r to the port therein, apvalye chamber in' which saidvalveis mounted `for rotation with the cylinder, said valvehalving aport in the circumference thereof in ,ccm munication with the saidpassagen'ay, and' inlet and exhaust ports in the ivallflofthe chamberwith which the port in thevalvesuccessively regi sters during therotatioiitli egeof.

2. In an internal combustion.` engine, a casing, a shaft mounted inbearings in the casing, a cvlin der secured to the sl/i'attwhose centercoincides With the axis of rotation of the cylinder, a pair of pi'stonsfin said cylinder in opposed relation4 and'arranged forsimultaneous actuation. by an exploded charge, a crank shaft for eachpiston mounted at opposite ends of the cylinder, a gear on each crankshaft, a stationary gear mounted Aon the casing concentricfyvith theshaft` With which the crank gears mesh. a port in said cylinder Whosecenter is coincident 'with 130 gear on the casing, the cranks 80 LettersPatent of the 95 inea the axis of rotation, a cylindrical valve securedto the cylinder in alinement with the shaft having a passageway incommunication with said port, a valve chamber in said casing forming abearing for the valve, said valve having a port inthe Wall thereof, apacking ring surrounding the port, and intake and exhaust ports in thevalve chamber with which the valve port successively registers duringits rotation.

3. ln an internal combustion engine, e cylinder mounted for rotationabout an axis, a pair of pistons in said cylinder in cpposed relationand arranged for simultaneous actuation by an exploded charge, a crankshaft for each piston mounted at opposite ends of the cylinder', a gearon each crank shaft, a stationary gear concentric with the axis ofrotation of -the cylinder y with which thercrank gears mesh, a port inthe cylinder between the pistons through which the cylinder receives theexplosive charge and exhausts the products of combustion, a cylindricalvalve having a passageway communicating' With said port, Said valvebeing mounted on the cylinder concentric to the axis of rotationthereof, a valve chamber in which the valve is seated, and a pluralityot' intake and exhaust ports in the wall of said chamber with which thevalve successively registers in timed relation with the operation of thepistons.

4;. ln an internal combustion engine, a,

a tearing in uw casing, a shaft mounted in to the shaft the casing, acylinder secured axis of which is coincident With the axis of rotationof the cylinder, a pair of pistons in said cylinder in opposed relationand arranged for simultaneous actuation by an exploded charge, a crankshaft for each piston mounted at opposite ends of the cylinder, a gearon each end of each crank shaft, stationary gears mounted on oppositesides of the casing, the center of which is coincident with the axis ci'rotation of the cylinder and with which the gears on the crank shaftmesh, said cylinder having a port between the pistons therein throughwhich it may receive an explosive charge and ezt-- haust the products ofcombustion, a cylindrical valve secured to the cylinder in alinementwith said shaft having a passageway in communication with said. port, avalve chamber in said casing forming a hearing for the valve, said valvehaving a port in Ythe wall thereof, and intake and exhaust ports in theWall of the valve chamber with which the valve port successivelyregisters during the rotation of the valve.

In testimony whereof, l, sign this speci ication in the presence of twowitnesses,

Joint J. Meravisn, JR.

Witnesses:

CrrAnLns E. lVIsNER, RICHARD Ansia-ls.

